The present invention relates to brake drums and, in particular, to improved finished and balanced brake drums and a method of finishing and balancing such brake drums.
Most brake drums for trucks and similar heavy duty vehicles are comprised of a cast iron brake drum that is subsequently machined to near final tolerances. Typically, the machined brake drum has a slight imbalance that needs to be corrected. Accordingly, the brake drum is subjected to a balancing operation after machining. Such balancing can comprise welding correcting weights to an outer surface of the drum or removing part of the brake drum.
In particular, brake drums that have an integral raised squealer band extending from near an open end of the brake drum can be balanced by removing a portion of the squealer band. Such balancing by removing a portion of the squealer band to a constant or substantially constant depth is shown in U.S. Pat. No. 5,483,855. Another method of balancing is shown in U.S. Pat. No. 4,986,149, which discloses the removing of a crescent or wedge of material from the integral squealer band. It is desirable to provide a machined and balanced brake drum, and a method for machining and balancing such a brake drum.